MXPA02007177A - Rubber composition for tyres comprising a reinforcing inorganic filler and an (inorganic filler elastomer) coupling system. - Google Patents

Abstract

The invention concerns a rubber composition for making tyres, based on at least a diene elastomer, a reinforcing inorganic filler, a polysulphide alkoxysilane as (inorganic filler elastomer) coupling agent with which is associated a 1,2 dihydropyridine and a guanidine derivative. The invention also concerns a tyre or semi finished product for tyres comprising said rubber composition. The invention further concerns an (inorganic filler diene elastomer) coupling system for a rubber composition based on reinforced diene elastomer of an inorganic filler, consisting of the combination of a polysulphide alkoxysilane, a guanidine derivative and a 1, 2 dihydropyridine.

Description

fe COMPOSITION OF RUBBER FOR TIRE COMPRISING A REINFORCING INORGANIC LOAD AND A COUPLING SYSTEM (INORGANIC LOAD / ELASTOMER) Description of the Invention The present invention relates to compositions of diene rubbers reinforced with a white or inorganic filler, intended particularly for manufacture of tires or semi-finished products for tires and in particular to the treads of these tires. 10 Since the economy of fuels and the need to protect the environment have become a priority, it is desirable to produce elastomers that have good mechanical properties and a hysteresis as small as possible in order to be able to use them in the form of 15 rubber compositions usable for the manufacture of various semi-finished products that enter the constitution of tires, such as for example sub-layers, calendering rubbers or flanks or treads and obtain tires with improved properties, possessing 20 mainly a reduced resistance to rolling. To achieve the objective, numerous solutions have been proposed, in principle essentially concentrated on the use of modified elastomers by means of agents REF. : 140641 star forging of functionalization, with carbon black as a reinforcing filler in order to obtain a good interaction between the modified elastomer and the carbon black. It is generally known that in order to obtain the optimum reinforcement properties conferred by a charge, it is convenient that the latter be present in the elastomer matrix in a final form which is at the same time as finely divided as possible. and distributed as homogeneously as possible 10 go away. However, such conditions can only be achieved when the load has a very good capacity, on the one hand to be incorporated in the matrix during the mixing with the elastomer and to deagglomerate, and on the other hand to disperse homogeneously in this U matrix. In a well-known way, carbon black presents the aptitudes, which does not happen in general in the case of white or inorganic fillers. For reasons of reciprocal affinities, the inorganic charge particles have a Annoying tendency, in the elastomeric matrix, to agglomerate with each other. These interactions have as a disastrous consequence limiting the dispersion of the load and therefore the reinforcement properties at a level that is substantially internal to what would theoretically be possible to achieve if they were obtained % faith < 5tiv. all links (load susceptible to being created during the mixing operation; these interactions tend, on the other hand, to increase the consistency of the paucho compositions and therefore to make their use more difficult. { "processability") in the raw state than in the presence of carbon black. Interest in rubber compositions reinforced with inorganic filler has however been strongly relaunched with the publication of European patent application EP-A-0501227 disclosing a sulfur vulcanizable diene rubber composition, reinforced with a particular precipitated sili highly dispersible type, which makes it possible to manufacture a tire or a tread which is improved in rolling resistance, without affecting the other properties and in particular those of adhesion, physical resistance and resistance to wear. The applications EP-A-0810258 and W099 / 28376 disclose diene rubber compositions t reinforced with other particular inorganic fillers, in this case aluminum aluminas or (oxide-) hydroxides specific, of high dispersibility, which also allow obtaining tires or treads that have the excellent compromise of contradictory properties. use of these specific inorganic fillers, or aluminoses, highly reinforcing, certainly It illustrates the employment difficulties of the rubber compositions that contain them, but this use remains "> However, it is more difficult than for rubber compositions conventionally charged with carbon black. In particular, it is necessary to use a coupling agent, also called a binding agent, whose function is to ensure the connection between the surface of TM) inorganic filler particles and the elastomer, while facilitating the dispersion of this inorganic filler within the elastomeric matrix By "coupling" agent (inorganic filler / elastomer), a known manner is People able to establish a sufficient connection, chemical and / or physical, between the inorganic filler and the elastomer, the coupling agent, at least bifunctional, has for example as a simplified general formula "YTX", in which: - Y represents a functional group (function "Y") that is OAPáz to physically and / or chemically bind to the inorganic charge, the link being able to be established, for example, in between a silicon atom of the coupling agent and the hydroxyl groups (OH) of the surface of the inorganic filler ip < > For example, surface sylloles when it comes to silica); - X represents a functional group (function "X") capable of physically and / or chemically bonding to the elastomer, for example by means of a sulfur atom; * - T represents a hydrocarbon group which makes it possible to join Y and X. Coupling agents should not be confused, in particular, with simple inorganic charge coating agents which, in a known manner, can comprise the Y function active against the inorganic charge but are devoid of the active X function against the elastomer. Coupling agents, mainly silica / elastomer, have been described in a large number of documents, the best known being bifunctional alkoxysilanes. Thus it has been proposed in patent application FR-A-2094859 to use a mercaptosilane for the manufacture of tire treads. It was quickly demonstrated and it is now well known that mercaptosilanes, and in particular β-mercaptopropyltrimethoxysilane or α-mercaptopropyltriethoxysilane, are capable of providing excellent coupling properties. Silica / elastomer, but that the industrial use of f ^ fs coupling agents is not possible due to the strong reactivity of its functions -SH which leads very tightly during the preparation of the rubber composition in an internal mixer to premature vulcanizations, also called "scorched" (in English it is called " scorching "), to very high Mooney plasticities, in the end to rubber compositions almost impossible to work and to employ industrially. To illustrate this impossibility of industrially using the coupling agents carrying the -SH function and the rubber compositions containing them, one can cite, for example, documents FR-A-2206330 and US-A-400259. To remedy this drawback, it has been proposed to replace these mercaptosilanes with alkoxysilanes f > Lisulfurized, primarily bis-trialkoxyl (C 1 -C 4) silylpropyl polysulfides, such as those described in the numerous patents or patent applications (see for example FR-A-2206330, US-A-3842111, US-A-3873489, US Pat. -A-3979103, US-A-3997581). These polysulfurized alkoxysilanes are generally considered today as the products that provide, for vulcanized silica-loaded, the best compromise in terms of safety against scorching, ease of use and reinforcing power. Among these polysulfides, bis-3 disulfide is particularly cited * -; trie! íoxysililpropilo (abbreviated TESPD), more - > > • f. J. > - particularly bis-3-triethoxysilylpropyl tetrasulfide (abbreviated TESPT) which is generally considered today as the coupling agent (inorganic / elastomeric filler) •: 5 dienic) more effective (and therefore the most widely used) in rubber compositions for tires, mainly those intended to form treads; It is marketed, for example, under the name "Si69" by the company Degussa. However, the applicant company has discovered during its investigations that the use of a 1,2-dihydropyridine in a small amount, in combination with a guanidine derivative, has the unexpected effect of activating the coupling function of the poly-sulfur alkoxysilanes, 15 that is, increase the efficiency of the latter more. Thanks to this activation, it is now possible to try to reduce in a sensible manner the amount usually used of polysulfurized alkoxysilanes. This is particularly advantageous because these alkoxysilanes are A very expensive part and, on the other hand, must be used in a significant amount, in the order of two to three times more, the amount of? -mercaptopropyltrialkoxysilanes necessary to obtain equivalent coupling properties; these well-known drawbacks have been . > For example, in US-A-5652310, US-A- ** t * frsri? ßl71 and US-A-5684172. Thus, the overall cost of the rubber compositions can be significantly reduced as well as that of the tires that contain them. Accordingly, a first object of the invention refers "to a rubber composition usable for the manufacture of tires, based on at least (i) a diene elastomer, (ii) an inorganic filler as a reinforcing filler, (iii) a polysulfurized alkoxysilane as agent 10 d coupling (inorganic filler / diene elastomer) to which are associated (iv) a 1,2-dihydroxypyridine and (v) a guanidine derivative. Another object of the invention is the use of a rubber composition according to the invention for the Manufacture of rubber articles, in particular tires or semi-finished products intended for such tires, these semi-finished products being chosen in particular in the group consisting of treads, sublayers intended for example to be placed under these treads, 20 crown layers, sidewalls, shell layers, heels, protectors, inner tubes and sealed inner tires for tubeless tires. The invention relates more particularly to the use of the rubber composition, due to its good is, for the manufacture of flanks or rolling treads. The invention also relates to a process for the preparation of a composition according to the invention, this method being characterized in that at least one diene elastomer is incorporated into (i); (ii) an inorganic filler as a reinforcing filler; (iii) a polysulfurized alkoxysilane; (iv) a 1,2-dihydroxypyridine and (v) a guanidine derivative, and because the assembly is thermomechanically kneaded, in one or several stages, until reaching a maximum temperature comprised between 120 ° C and 190 ° C. The composition according to the invention is particularly adapted to the manufacture of tire tread bands for the purpose of equipping passenger vehicles, 4x4 vehicles, carriages, two-wheeled vehicles and heavy goods vehicles, airplanes, public works, agricultural machines or of maintenance, these treads can be used during the manufacture of new tires or for the retreading of used tires. The invention also relates to these tires and these semi-finished rubber products by themselves when they comprise a rubber composition according to the invention. The invention relates in particular to the bands of , - A, > x. li? f, áe tires; Thanks to the compositions of the invention, these treads have at the same time a low rolling resistance and a high resistance to wear, even in the presence of a reduced proportion of coupling agent constituted by alkoxysiloxane-sulphide. The invention also relates to, in itself, to a coupling system (inorganic filler / diene elastomer) for a diene rubber composition reinforced with an inorganic filler, usable for the manufacture of tires, the system being constituted by the association of a polysulfurized alkoxysilane, a 1, 2-dihydroxypyridine and a guanidine derivative. Another subject of the invention is the use of the coupling system (inorganic filler / diene elastomer) in a tire rubber composition. Another subject of the invention is the use in combination of a 1,2-dihydroxypyridine and a guanidine derivative, in a rubber composition reinforced with an inorganic filler, to activate the coupling function (inorganic filler / diene elastomer) of the polysulfurized alkoxysilanes. The subject of the invention is finally a process for coupling an inorganic filler and a ? < Dienic lastomer, in a rubber composition, this method being characterized in that it is incotporated to (i) at least one diene elastomer, at least: (ii) an inorganic filler as a reinforcing filler; (iii) an alkoxysilane 5-olisulfurized; (iv) a 1,2-dihydroxypyridine and (v) a guanidine derivative, and because the assembly is thermomechanically kneaded, in one or more stages, until reaching a maximum temperature comprised between 120 ° C and 190 ° C. The invention as well as its advantages will be understood 10 easily in light of the description and the following examples of embodiment, as well as the figures of the drawings relating to these examples which represent curves of variation of the module (in MPa) as a function of the elongation (in%) for different rubber compositions dienic 15 according to the invention or not. 1. MEASUREMENTS AND TESTS USED Rubber compositions are characterized before and after cooking, as indicated below: & . Mooney 2Q plasticity An oscillating consistometer is used as described in the standard AFNOR-NFT-43005 (November 1980). The measurement of the Mooney plasticity is made according to the following principle: the composition in the raw state (that is, before the cooking) is molded in a cylindrical enclosure heated to | 0 ° C. After one minute of preheating, the rotor rotates inside the specimen at 2 revolutions / minute and the useful torque is measured to maintain this movement after 4 minutes of rotation. The Mooney plasticity (ML 1 + 4) is expressed in "Mooney unit" (UM, with 1 MU = 0.83 newton.metro) 1-2. Scorch time The measurements are made at 130 ° C, in accordance with the AFNOR-NFT-43004 standard (November 1980). The evolution of the consistometric index as a function of time allows to determine the scorching time of the rubber compositions, appreciated according to the aforementioned standard by the parameter T5, expressed in minutes, and being defined as the time necessary to obtain an increase of the index Consistometric (expressed in UM) of 5 units above the minimum value measured for this index. 1-3. Tensile tests These tensile tests make it possible to determine the elastic stresses and the properties at break. Unless otherwise indicated, they are carried out in accordance with the AFMOR-NFT-46002 standard of September 1988. The nominal elongation modules (in MPa) at 10% elongation are measured in second elongation (ie after an accommodation cycle) (referred to as MIO), 100% elongation (M100) and 300% elongation (M300). Tensions are also measured in the t > s < s & * 3 »a break (ßn Mpa) and elongations at break (in%). All these tensile measures are carried out under normal temperature and hygrometry conditions according to the AFNOR-NFT-40101 standard (December 1979) .A treatment of the traction registers also allows tracing the curve of the module as a function of elongation ( see appended figures), the module used being the true secant module measured at the first elongation, calculated referring to the actual section of the specimen and not to the initial section as above for the nominal modules 1 * 4. Hysteresis losses Hysteresis losses (called PH) are measured by rebound at 60 ° C in the 6th shock and are expressed in% according to the following relationship (0: energy supplied, Wi: energy restored): PH (%) = 100 [(Wo -W?) / Wo3 II. CONDITIONS OF MODALITY OF THE INVENTION The rubber compositions according to the invention are based on the following constituents: (i) a. { at least one) diene elastomer (component A), (ii) one (at least one) inorganic filler as reinforcing filler (component B) (iii) one (at least one) polysulfurized alkoxysilane (component • - * "C - abbreviated ASPS) as a coupling agent (load 'organic' / diene elastomer), to which they are associated, to '* - activate coupling, (iv) one (at least one) 1, 2- dihydroxypyridine (component D-abbreviated 1,2-DHP) and i-5 '\ (v) an (at least one) guanidine derivative (component E), Naturally, by the term "based on" composition, it is necessary to understand a composition comprising the mixture and / or the reaction product in itself of the different constituents used, some of these 10 constituents being susceptible of, or destined to react with each other, at least partially, during the different operations of manufacture of the composition, mainly in the course of its vulcanization. The coupling system according to the invention is constituted as such by a coupling agent ASPS, preferably majority (ie with more than 50% by weight) and a coupling activator formed by the association of a 1,2-DHP and a guanidine derivative. II-l. Diene Elastomer (component A) By "elastomer" or "diene" rubber is understood in a known manner an elastomer derived at least in part (ie, a homopolymer or a copolymer) from diene monomers, (monomers bearing two carbon-carbon double bonds) , conjugated or not).

* Of Ja & general, it is understood in this text by * the "essentially unsaturated" diene turner, a diene elastomer derived at least in part from conjugated diene monomers, having a proportion of residues or units of diene origin (conjugated dienes) which is greater than 15% (mole%). Thus, for example, as diene elastomers such as butyl rubbers or copolymers of diene and alpha-olefins type EPDM do not fall within the above definition and can be mainly qualified as "essentially saturated" diene elastomers (low or very low proportion of remains of dienic origin, always lower than 15%). In the category of "essentially unsaturated" diene elastomers, it is understood in particular by "strongly unsaturated" diene elastomer a dieneic elastomer having a proportion of diene residues (conjugated dienes) which is greater than 50%. Given these definitions, it is understood more particularly by diene elastomer capable of being used in the compositions according to the invention: (a) - any homopolymer obtained by polymerization of a conjugated diene monomer having from 4 to 12 carbon atoms; ffcji - any copolymer obtained by copolymerization of several dienes conjugated to each other or to one or more vinyl aromatic compounds having from 8 to 20 carbon atoms; fc) - a ternary copolymer obtained by copolymerization of ethylene, of an α-olefin having from 3 to 6 carbon atoms with a non-conjugated diene monomer having from 6 to 12 carbon atoms, such as, for example, the elastomers obtained from of ethylene, propylene with a non-conjugated diene monomer of the aforementioned type, such as -mainly 1,4-hexadiene, ethylidene norbornene and cyclopentadiene; (d) - a copolymer of isobutene and isoprene (butyl rubber), as well as halogenated versions, in particular bleached or brominated, of this type of copolymer. Although applied to any type of dielectrically elastomer, it will be understood by those skilled in the art of tires that the present invention, particularly when the rubber composition is intended for a tire tread, is primarily used with essentially diene elastomers. unsaturated, in particular of type (a) or (b) above. Suitable conjugated dienes are 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-d? (C? -C5 alkyl) - * < * '3 ** but dienes, such as for example 2, 3-dimethyl-1, 3-t-tadiene, 2, 3-diethyl-l, 3-butadiene, 2-methyl-3-ethyl-1, 3 ~ butadiene, 2-methyl-3-isopropyl-l, 3-butadiene, aryl-1, 3-butadiene, 1,3-pentadiene and 2,4-hexadiene. As compounds For example, styrene, ortho-, meta-, para-methylstyrene, the commercial mixture "vinyl toluene", para-tertiarybutylstyrene, methoxystyrenes, chlorostyrenes, vinylmesitylene, divinylbenzene and vinylnaphthalene are suitable. The copolymers can contain between 99% and 20% by weight of diene units and between 1% and 80% by weight of vinyl-aro units. The elastomers can have any microstructure that is a function of the polymerization conditions used, mainly by the presence or 15 not of a modifying and / or randomizing agent and the amounts of modifying and / or randomizing agent employed. The elastomers can be, for example, block, statistical, sequenced, microsequenced and prepared in dispersion or in solution; they may be coupled and / or have a star shape or also functionalized with a coupling and / or star formation or functionalization agent. Preferably the polybutadienes and in particular those that have a content of 1,2 units emre di or between 4% and 80% < IONS having a content of cis-1,4, greater than 80%, the polubensins, the butadiene-styrene copolymers and in particular those having a styrene content between 5% and 50% by weight and more particularly between 20% and 50% by weight; % and 40%, a content of 1,2 bonds of the butadiene part comprised between 4% and 65%, a content of trans-1,4 bonds comprised between 20% and 80%, the butadiene-isoprene copolymers and mainly those having a content of isoprene comprised between 5% and 90% by weight and a vitreous transition temperature (Tg) of -40 ° C to -80 ° C, isoprene-styrene copolymers and mainly those having a styrene content comprised between 5% and 50% by weight and a Tg comprised between -25 ° C and -50 ° C. In the case of the butadiene-styrene-isoprene copolymers, those having a styrene content between 5% and 50% by weight and more particularly between 10% and 40%, an isoprene content of between 15%, are particularly suitable. and 60% by weight and more particularly between 20% and 50%, a butadiene content comprised between 5% and 50% by weight and more particularly comprised between 20% and 40%, a content of 1.2 units of the butadiene part between 4% and 85%, a content of trans-1,4 units of the butadiene part between 6% and 80%, a content of 1,2 units plus 3,4 of the & $ ¥ $ iso ica ré between 5% and 70% and a content of "trans-1,4 units of the isoprene part of between 10% and 50% and more generally any butadiene-styrene-isoprene? have a Tg between -2Q ° C and -70 ° C. In short, particularly preferably, the diene elastomer of the composition according to the intention is chosen from the group of elastomers strongly unsaturated diene consisting polibu adienos (BR), polyisoprenes (IR), natural rubber (NR), compolímeros of butadiene, isoprene copolymers and mixtures of these elastomers. The copolymers are more preferably selected from the group consisting of butadiene-styrene copolymers (SBR), isoprene-butadiene copolymers (BIR), isoprene-styrene copolymers (SIR) and isoprene-butadiene-styrene (BIR). The composition according to the invention is particularly intended for a tire tread, whether it is a new or used tire (retreaded). In the case of a passenger car tire, component A is for example an SBR or a combination (mixture) SBR / BR, SBR / NR (or SBR / IR), or even BR / NR (or BR / IR) . In the case of an SBR elastomer, an SBR having a styrene content of between 20% and í í < * - ea-pepo, a link content? vinyl of the part e «! Butadieni-ca comprised between 15% and 65%, a content of Tirans-1,4 bonds comprised between 15% and 75% and a Tg comprised between -20 ° C and -55 ° C. The SBR copolymer produced 5 preferably in solution, using appropriate mixed with a polybutadiene (BR) preferably having more than 90% cis-bond-1, 4. In the case of a tire for utility vehicle, especially for a vehicle " heavy load, "meaning 10 subway car, bus, special transport vehicles - road (trucks, tractors, trailers), off-road vehicles, component A is chosen for example in the group consisting of natural rubber; synthetic polyisoprenes, isoprene copolymers ÍS (isoprenobutadiene, isoprene-styrene, butadiene-styrene, isoprene) and mixtures of these elastomers. In such a case, the component A may also be constituted, in whole or in part, by another strongly unsaturated elastomer such as, for example, an SBR elastomer. 20 According to another advantageous embodiment of the invention, especially when it is intended for a tire sidewall, the composition according to the invention may contain at least one essentially saturated diene elastomer, in particular at least one EPDM copolymer, where e) t copolymer used or not mixed with one or more of the strongly unsaturated diene e? tonicmers mentioned above. Naturally, the compositions of the invention may contain a single diene elastomer or a mixture of several diene elastomers, whereby the or diene elastomers used in association with any type of synthetic elastomer other than diene, even with polymers other than elastomers, for example, thermoplastic polymers. II-2. Reinforcing load (component B) The white or inorganic load used reinforcing load bed can constitute all or a part only of the total reinforcing load, in the latter case associated for example to carbon black. Preferably, in the rubber compositions according to the invention, the reinforcing inorganic filler constitutes the majority, ie more than 50% by weight of the total reinforcing filler, more preferably more than 80% by weight of this total reinforcing filler. In the present application, "reinforcing inorganic filler" is understood, in known manner, as an inorganic or mineral filler, whatever its color and origin. { natural or synthetic), also called "white" or "white" charge, as opposed to carbon black, being eapaz this inorganic load of reinforce by itself, with no other means than an intermediate coupling agent, a rubber composition intended for the manufacture of tires, in other words able to replace, in its reinforcing function, a conventional load of quality carbon black for tires. Preferably, the reinforcing inorganic filler is a mineral charge of the siliceous or aluminous type, or a mixture of these two types of fillers. The silica (SiO2) used can be any reinforcing silica known to those skilled in the art, especially any precipitated or pyrogenic silica having a BET surface as well as a CTAB surface area both less than 450 m2 / g, preferably 30 to 400 m2 / g. . HE Preferred precipitated highly dispersible silicas (referred to as "HDS"), particularly when the invention is applied to the manufacture of tires having low rolling resistance; By highly dispersible silica, it is understood in a known manner any silica having an important aptitude for deagglomeration and dispersion in an elastomeric matrix, observable in a known manner by electron microscopy or optics, in thin sections. Coto0 non-limiting examples of the highly dispersible preferential silicas, mention may be made of the BV3380 and Ultrasil silicas *? $ 0Ó from the company Degussa, silicas Zeosil 1165 MP and lll5 MP from the company Rhodia, silica Hi-Sil 2000 from the company PPG, silicas Zeopol 8715 or 8745 from the company Huber and precipitated silicas treated, such as for example 5 the silicas "doped" with aluminum described in the application EP-A-0735088. The reinforcing alumina (A1203) preferably used is a highly dispersible alumina having a BET superfiber ranging from 30 to 400 m2 / g, more preferably between 60 and 250 m2 / g, a mean particle size at most equal to 500 nm , more preferably at most equal to 200 nm, as described in the aforementioned EP-A-0810258. As non-limiting examples of the reinforcing aluminas, mention may be made in particular of the aluminas 5 A125, CR125 (Bai owski company), APA-100RDX (Condea company), Alu inoxid C (Degussa company) or AKP-G015 (Sumitomo Chemicals). The invention can also be put into practice and the specific aluminum (oxide-) hydroxides, such as those described in * > : "'application W099 / 28376. It is indifferent to the physical state in which the reinforcing inorganic filler is present, either in the form of powder, microbeads, granules or even balls.

.HE*, < the $ of different reinforcing inorganic fillers, * eh particularly highly dispersible siliceous and / or luminescent fillers, such as those described above. When the rubber compositions according to the invention are used as tire treads, the reinforcing inorganic filler used, in particular if it is silica, preferably has a BET surface comprised between 60 and 250 m2 / g, more preferably between 80 and 230 m2 / g. The reinforcing inorganic filler can also be used in combination (mixing) with carbon black. All carbon blacks are suitable as carbon blacks, especially blacks of the HAF, ISAF, SAF type conventionally used in tires and particularly in tire treads. As non-limiting examples of such blacks, mention may be made of blacks N115, N134, N234, N339, N347 and N375. The amount of carbon black present in the total reinforcing filler can vary within wide limits, this amount preferably being less than the amount of reinforcing inorganic filler present in the rubber composition. Preferably, the proportion of total reinforcing filler (reinforcing inorganic filler plus carbon black, if applicable) is between 20 and 300 pee, more preferably between 30 and 150 pee, even more preferably 50 to 130 pee (parts by weight percent elastomer), the optimum value being different depending on the nature of the reinforcing inorganic filler used and according to the applications considered; the expected level of reinforcement in a bicycle tire, for example, is in a known manner much lower than that required for a tire which is capable of running at high speed for a long time, for example a motorcycle tire, a tire for a passenger vehicle or a utility vehicle, such as a heavy-duty vehicle. For treads of tires capable of rolling at high speed, the amount of reinforcing inorganic filler, in particular if it is silica, is preferably in a range of 50 to 100 pee.

In the present disclosure, the BET specific surface area is determined in a known manner, according to the method of Brunauer-Emmet-Teller described in "The Journal of the American Chemical Society ", Vol 60, page 309, February 1938 and corresponds to the standard AFNOR-NFT-45007 (November 1987), the CTAB surface area is the external surface determined according to the same standard AFNOR-NFT-45007 of November 1987 II-3. Coupling agent (component C) The coupling agent used in the rubber compositions according to the invention is an ASPS, which is a carrier in a known manner of two types of functions referred to herein as "Y" and "X", which can be the inorganic charge by means of the "Y" function (alkoxysilyl function) and on the other hand in the elastomer by means of the "X" function (sulfur function). ASPS are widely known to those skilled in the art as a coupling agent (inorganic filler / diene elastomer) in rubber compositions for the manufacture of tires. Particularly used are polysulfurized alkoxysilanes, referred to as "symmetric" or "asymmetric" according to their particular structure, such as those described in US-A-3,842,111, US-3,873,489, US-A-3,978,103, US Pat. -A-3,997,581, US-A-4,002,594, US-A-4,072,701, US-A-4,129,585, or in the most recent patents or patent applications US-A-5,580,919, US. -A-5,583,245, US-A-5,650,457, US-A-5,663,358, US-A-5,663,395, US-A-5,663,396, US-A-5,674,932, US-A-5,675. 014, US-A-5,684,171, US-A-5,684,172, US-A-5,696,197, US-A-5,708,053, US-A-5,892,085 and EP-A-1,043,357 which describe in detail the known compounds. . ' i For the implementation of the invention they agree * • particularly, without the following definition being limiting, ASPS referred to as "symmetrical" corresponding to the following general formula (I): (I) Z - A - Sn - A - Z, in which - n is a whole number of 2 to 8 (preferably 2 to 5) - A is a divalent hydrocarbon radical; - Z responds to one of the following formulas: 10 R1 R1 R2 -Si- R1 -Si- R2 -Si- R2 fc fc fc wherein: "R5" - the radicals R1, substituted or unsubstituted, identical or different from each other, represent a C1-C18 alkyl group, C5-C8 cycloalkyl or Cd-C8 aryl; - the radicals R 2, substituted or unsubstituted, identical or different from each other, represent a C 5 -C 18 alkoxy or C 5 -C 18 cycloalkoxy group In the case of a mixture of ASPS corresponding to formula (I) above, principally the usual commercially available mixtures, it will be understood that the average value of "n" is a fractional number, preferably comprised 2S * , 81 range from 2 to 5. • v-? "The radical A, substituted or unsubstituted, is preferably a divalent, saturated or unsaturated hydrocarbon radical, comprising 1 to 18 carbon atoms. .5 Suitable alkylene groups of Ci-Ciß or arylene groups of C6-C? 2, more particularly Ci-Cio alkyl, X mainly C2-C4, in particular propylene. The radicals R1 are preferably alkyl, Ci-Ce, cyclohexyl or phenyl groups, mainly alkyl groups of M C? ~ C4, more particularly methyl and / or ethyl. The radicals R 2 are preferably C 1 -C 8 alkoxy or C 5 -C 8 cycloalkoxy groups, more particularly methoxy and / or ethoxy. Preferably the ASPS used is a polysulfide, particularly a disulfide or tetrasulfide, of bis-15 'to & coxyl (C1-C4) silylalkyl (C1-C10) / more preferably even bis- ((C1-C4) alkylsilylpropyl), in particular bis- > (Trialkoxy (C1-C4) silylpropyl), especially bis (3-trie »• fcoxysilylpropyl) or bis (3-trimethoxysilylpropyl). Bis (triethoxysilylpropyl) disulfide or TESPD, of • 20 formula [(C2H50) 3Si (CH2) 3S] 2, is marketed, for example, by the company Degussa under the names S266 or S75 (in the second case, in the form of a di-sulfide mixture (at 75% by weight) and polysulfide), and also by society Witco with the name Silgues A1589. The tetrasulfide of íf -A, ftts (triethoxysilylpropyl) or TESPT, of formula t (C2H50) 3Si (CH2) 3S2] 2, is marketed, for example, by the company Degussa under the designation Si69 (or X50S when it is supported at 50% by weight on carbon black ) or 5 also by the Witco company with the name Silques A1289 (in both cases commercial mixture of polysulfides with a mean value for n that is close to 4). The TESPT is preferably used. But an advantageous embodiment of the invention consists in using the TESPO, 10: certainly less active than the TESPT when it is used alone, but whose efficiency is significantly improved by the presence of the 1,2-DHP and the guanidine derivative. As another example of organosilane ASPS, there may be mentioned, for example, an organosilane of oligomer or polymer type, as described, for example, in applications 096/10604 or DE-A-4,435,311, and which corresponds to the following formula: where x = 1 to 8, m = 1 to 200, and OEt represents the ethoxy radical.

$ In the rubber compositions according to the invention, the ASPS content is preferably between 0.5 and 15% by weight with respect to the amount of reinforcing inorganic filler, that is, in the S * 4 most of the cases, between 1 and 10 pee, more preferably between 3 and 8 pee. But it is usually desirable to use the least amount possible. The presence of 1,2-DHP and the guanidine derivative, in these compositions, advantageously makes it possible to be able to use the ASPS in a proportion ñ preferably lower than 10%, even lower than 8% by weight with respect to the amount of inorganic filler reinforcing proportions between 4 and 8% are thus advantageously possible. The ASPS could be previously grafted (through the * 15 function "X") in the diene elastomer of the composition of the invention, the elastomer thus comprising, thus functionalized or "pre-coupled", the free "Y" function for the reinforcing inorganic filler. The ASPS could also be previously grafted (using the "Y" function) in the load Inorganic reinforcing agent, the pre-coupled charge can then be joined to the diene elastomer by means of the free function "X". However, it is preferred, mainly for reasons of better use of the compositions in the raw state, to use - • * V * coupling agent well grafted on the load - Reinforcing protein, or in free (ie non-grafted) state, such as 1,2-DHP and the guanidine derivative associated with it in the coupling system according to the invention. II-4. Activation of coupling "The coupling system according to the invention consists of the coupling agent ASPS defined above and a coupling activator of this-10-alkoxysilane. By coupling "activator" is meant here a body (a compound or an association of compounds) which, when mixed with the coupling agent, increases the efficiency of the latter. The coupling activator used according to the invention is formed by the association of a 1,2-DHP and a guanidine derivative • v. A) 1,2-DHP (component D) - * - 'The dihydropyridines (abbreviated "DHP"), especially the 1,2-dihydropyridines (abbreviated here 20"1,2-DHP") are well known to the experts in The technique. DHPs have hitherto been used essentially as additives in adhesive compositions, stabilizing agents, polymerization activators or even vulcanization accelerators (see, for example, EP-A0334377; 4-05027033; EP-A-0794219, EP-A-0667491; -A-4450030 and - flg-A-5747601). A 1,2-DHP responds in a known manner to the general formula (I I) that follows: (II) wherein the radicals R3 to R9, identical or different from each other are preferably chosen from hydrogen, a hydrocarbon group, the OH, CN, NH2, SH groups or the halogens. The radicals R3 to R9 are chosen more preferably between "lS hydrogen and hydrocarbon groups preferably having 1 to 20 carbon atoms, which may be * e) linear, cyclic or branched groups, substituted or unsubstituted. As examples of such hydrocarbon groups can C-Cis alkyls, C3-Ce cycloalkyls, C7-C2al arylalkyl, C6-C8 aryls, C7-C2alkylopls, C2-C8 alkenyls, C- alkoxyls C? 8, SR groups, NR2, MHR, COR, COOR, COOH, CONR2, CONHR, CONH2, S? R3 and Sl (OR3).

More preferably the radicals R > 3 a, ft9 are chosen from hydrogen, C1-C10 alkyls (mainly methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl), cycloalkyls of 3_C8 (mainly cyclopentyl, cyclohexyl, cycloheptyl), arylalkyl of C7-C? 2 (mainly benzyl, phenyl-ethyl), C6-C ?2 aryls (mainly phenyl, naphthyl), C7-C14 alkylaryl (mainly toluyl, xylyl, ethyl-phenyl) and C2-C al alkeny (mainly propenyl) , butenyl). On the other hand, two of these radicals R3 to R9 (for example R5 and R7) could be considered together to form a cycle in which a heteroatom chosen for example between S, O and N could possibly be present. -DHP has been discussed in detail in "Development in Dihydropyridine Chemistry" by J. Kuthan and A. Kurfurst, Ind. Eng. Chem. Prod. Res. Dev., 1982, 21, p. 191-261. The compounds can be obtained from pyridine derivatives, for example by reduction of the corresponding pyridinium salts or by the Hantzsch process. The compounds are also synthesized in a known manner by condensation, in the presence of a catalyst (for example an acid), a primary amine and an aldehyde whose carbon in a of the carbonyl function carries at least two hydrogen atoms; this reaction is described for example in Chem. Commun., 1971, 476, by H. dh íftan and J. Rowe and Tetrahedron Lett., 3653,, (1971) by, G. KS? W, E. Michener and K. C. Ramey. Thus, in the case of one of 1 $ condensates (aldehyde-amine), the radicals R6, R8 and at least one of the radicals R3 or R4 represent hydrogen. It is known that the reaction of an aldehyde with an amine, especially in the case of an aliphatic aldehyde, can lead to numerous side products due to the strong propensity of these aldehydes to condense with themselves (aldolisation reaction described for example in Advanced Organic Chemistry , 4th, by J. March, p.937, Johns Wiley &Sons). This is the reason why, when 1,2-DHP is used in the form of an aldehyde-amine condensate (ie, a mixture of condensation products of the aldehyde and the amine) it is preferred that the 1,2- DHP then represents the majority constituent (ie the one with the highest weight content) of the condensate. Any primary, aliphatic or aromatic amine comprising from 1 to 18 carbon atoms can be used, for example ethylamine, n-butylamine, n-pentylamine, cyclopentylamine, n-hexylamine, cyclohexylamine, n-octylamine, n-decylamine, n- dodecylamine, n-hexadecylamine, octadecylamine, aniline, toluyl amines or xylil. Among the aldehydes, there may be mentioned any C2-C2 aldehyde (mainly acetaldehyde, propionaldehyde, n- Isutiraldehyde, pentane, cyclopentanal, hexanal, cyclohexanal, n-heptanal, n-decanal and n-dodecanal). More preferably, especially for reasons of purity of the condensates, a short carbon chain aldehyde of C3-6 will be chosen: namely propionaldehyde, butyraldehyde (butanal), valeraldehyde (pentanal) or hexaldehyde (hexanal). According to a particularly preferred embodiment of the invention, the 1,2-DHP used is an N-phenyl-1,2-dihydropyridine, that is to say that the radical R 9 is a substituted or unsubstituted phenyl radical. This means that, in the case of a condensate (aldehyde / amine), the amine used is a phenylamine (substituted or unsubstituted phenyl radical), in particular aniline (unsubstituted phenyl). As examples of 1,2-DHP usable in the compositions of the invention, mention may be made of 3,5-dipentyl-1,2-dihydro-1-phenyl-2-hexylpyridine, available for example in the form of a heptaldehyde condensate. aniline, which corresponds to the following formula (II-1): (ii-D) As a more preferred example, 3,5-diethyl- ? J "$ ^. I 2-dil? Id and: © -l-f phthyl-2-propylpyridine (II-2) As examples of condensates (aldehyde / amine) which can be used in the compositions of the invention, URj cite the heptaldehyde-aniline condensates of society * '* Uniroyal Chemical (designation "Hepteen Base"), the butyraldehyde-aniline condensates from the company RT Vanderbilt (for example the designation "Vanax 808" - purity -4? 1,2-DHP of approximately 30%), all these 1'5 condensates marketed as vulcanization accelerators. Preferably condensates (aldehyde / amine) whose content or purity in 1,2-DHP (% by weight) is as high as possible, preferably greater than 50%, more preferably greater than 70%. As a particularly preferred example, the condensation product of aniline and butyraldehyde which, after purification, consists predominantly of a 3,5-diethyl-1,2-dihydro-1-phenyl-2-propylpyridine of formula (II), will be cited. -2) previous; , this product is marketed by R.T. Vanderbilt with the denomination Vanax 808 HP (purity in 1,2-DHP of at least 85%). Those skilled in the art, after having knowledge of the invention, will know how to adjust the optimum content of 1,2-DHP depending on the application considered, the inorganic filler used and the nature of the elastomer used, in a range comprised preferably between 0.1 and 3 pee, more preferably between 0.2 and 1 pee. Proportions of 0.2 to 0.6 pee, for example, are advantageously possible for compositions intended for tire treads for passenger vehicles. Naturally, the optimal content of 1,2-DHP will be chosen, firstly, based on the amount of ASPS used. Preferably, in the coupling system according to the invention, the amount of 1,2-DHP represents between 1% and 20% by weight with respect to the amount of ASPS; below the minimum proportions indicated there is a risk of being insufficient, while beyond the maximum proportions indicated above, improvements in the coupling are no longer observed, while the costs of the composition increase and there is a risk of the be exposed to the dangers of singeing. For the reasons stated above the amount of 1,2- * t * 2§ -.ßP is more preferably comprised between 3% and 17.5% with respect to the ASPS. Preferably, in the rubber compositions according to the invention, the total amount of ASPS and 1,2-DHP represents 5 less than 10%, more preferably between 5% and 10% by weight with respect to the amount of reinforcing inorganic filler. This corresponds in most cases to a proportion of . { ASPS + 1,2-DHP) comprised between 1 and 10 pee, more preferably between 4 and 9 pee. 10 B) Guanidine derivative (component E) The second component necessary for coupling activation is a guanidine derivative, ie a substituted guanidine. The substituted guanidines are well known to those skilled in the art, in particular as vulcanization agents, and have been described in numerous documents (see for example "Vulcanization and vulcanizing agents", W. Hofmann, Ed. McLaren and Sons Ltd , (London), 1967, pp. 180-182; EP-A-0683203 or US-A-5,569,721). In the compositions according to the invention, N, N'-d? Phen? Lguanidine (abbreviated "DPG") which corresponds to the following particular formula (III-l) is preferably used: (III-l) But guanidine derivatives can also be used A, other than DPG, in particular other derivatives of % aromatic guanidine corresponding to the following general formula (III): (III) Arl-HN NH "Ar2 eft which Ar1 and Ar2 represent an aryl group, substituted or unsubstituted, preferably a phenyl group, and R10 represents a hydrogen or a hydrocarbon group, As an example of compounds corresponding to the general formula ftll) above , there may be mentioned, in addition to the DPG already mentioned, the triphenylguanidine (TPG) or even the di-o-tolylguanidma (DOTG) of the formula (III-2): * (III-2) jEfi? PS compositions according to the invention, the * guanidine derivative comprises preferably J between 0.5% and 4% by weight with respect to the weight of inorganic reinforcing filler 1, more preferably between 1% and 3%, is 9 preferably say between 0.25 and 4 pee, more preferably even between 0.5 and 2 pee. Below the minimum proportions indicated, the activation effect has the risk of being insufficient, while beyond the maximum values indicated there is usually no improvement of the 10 coupling, also exposing to scorching hazards. Preferably, in the compositions of the invention, the coupling system constituted by the ASPS and the "coupling activator (1,2-DHP + guanidine derivative) represents altogether between 2% and 20%, more preferably between 15 5% and 15% by weight with respect to the amount of reinforcing inorganic filler. In most cases this coupling system has proved sufficiently satisfactory, for the needs of the compositions - designed for the manufacture of tires, in particular the 20 added to the treads of tires for passenger cars, for a proportion of less than 12%, even less than 10% by weight with respect to the amount of reinforcing inorganic filler. With regard to the weight of the diene elastomer, the proportion of the coupling system • v-X * • k r t Item .:. According to the invention, it is preferably comprised between 2 and "1 - 1S pee, more" preferably between 5 and 10 pee. II-5. Miscellaneous additives Of course, the rubber compositions according to the invention also comprise all or part of the additives commonly used in sulfur crosslinkable diene rubber compositions and intended for the manufacture of tires, such as plasticizers, pigments, lubricants, protection of tipa antioxidants, 10 antiozonates, a cross-linking system based on either sulfur, either sulfur donors, and / or peroxide and / or bis- aniaimides, vulcanization accelerators, vulcanization activators, dilution oils, etc. The reinforcing inorganic filler can also be associated, if necessary, with a conventional non-reinforcing white filler, for example particles of clay, bentonite, talc, clay, kaolin or titanium oxides. The compositions according to the invention may also contain, as a supplement to the ASPS, coating agents (comprising, for example, the only Y function) of the reinforcing inorganic filler, or more generally employment aid agents capable of improving in a known his power of employment in crude state, thanks to an improvement of the dispersion of the inorganic load in the matrix of a decrease in the viscosity of the these agents being for example alkylaxyxysilanes (mainly alkyltriethoxysilanes), polyols, polyethers (for example polyethylene glycols), primary, secondary or tertiary amines, hydrolyzable hydroxylated polyorganosiloxanes, for example a, β-dihydroxy-polyorganosiloxanes (mainly α, β-dihydroxy-polydimethylsiloxanes) . These compositions could also contain other coupling agents, in addition to the ASPS. II-6. Preparation of rubber compositions The compositions are manufactured in appropriate mixers, in a manner known to those skilled in the art, typically using two successive preparation operations, a first high temperature thermo-mechanical working operation, followed by a second working operation. mechanical at a lower temperature, such as those described, for example, in the aforementioned EP-A-0501227, EP-A-0810258 or 099/28376. The first operation of thermomechanical work (sometimes described as "non-productive" operation) is intended to mix intimately, by kneading, the different ingredients of the composition, with the exception of the vulcanization system. The operation is performed on a device suitable mixing, such as an internal mixer or an extrusion machine until reaching, under the effect of mechanical work and the strong shearing imposed on the mixture, a maximum temperature generally comprised between 5 120 ° C and 190 ° C, preferably comprised between 130 ° C and 180 ° C. This first operation may itself comprise one and only one or several stages of thermomechanical work, separated for example by one or several intermediate stages of cooling. 10 The different ingredients of the composition, elastomer (s), reinforcing filler and its coupling system, and the various other components ("additives") can be incorporated into the mixer once or several times, or during the first stage thermomechanical, well staggered in the 15 course of the different thermomechanical stages; according to the case. The total duration of this thermomechanical work (typically between 1 and 20 minutes, for example between 2 and 10 minutes) is chosen according to the particular operating conditions, in particular of the maximum temperature chosen, 20? E the nature and volume of the constituents, it being important that a good dispersion of the different ingredients that react with each other is obtained in the elastomeric matrix, thus allowing from the beginning a good use of the composition in the raw state, then a sufficient level cooking, by the ca? -g »reinforcer and "> **" JSfr Intermediate coupling system. After cooling of the thus obtained * mixture, it is then carried out a second working operation - 5 a &, at a lower temperature. This operation, sometimes described as a "productive" operation, consists in incorporating the vulcanization system (or crosslinking) by mixing in an adapted device, for example a tool with cylinders, the operation is carried out for an appropriate time (typically between 1 and 30 minutes, between 2 and 5 minutes) and at a sufficiently low temperature (typically lower than 120 ° C, for example between 60 ° C and 100 ° C) in all cases lower than the vulcanization temperature of the mixture, so as to prevent premature vulcanization (scorched) According to a preferred embodiment of the method according to the invention, all the basic constituents of the compositions according to the invention, namely: fii) the reinforcing inorganic filler and the coupling system according to the invention constituted by the association X '"$ e (iii) ASPS, of (iv) 1,2-DHP and of (v) the derivative of "- guanidine, are incorporated into (i) the diene elastomer in the course of the first operation called non-productive, that is to say that they are introduced in the mixer and that they are kneaded Thermometaminent, in one or several stages, at least these different base constituents until reaching a maximum temperature comprised between 120 ° C and 190 ° C, preferably comprised between 130 ° C and 180 ° C. 'As an example, the first (non-productive) operation is carried out in successive stages of a duration of 1 to 5 minutes, in a conventional internal pallet mixer of the "Banbury" type whose initial tank temperature is of the order of 60 ° C . First the elastomer (or the elastomers) is introduced, and then, after for example 1 minute of kneading, the reinforcing filler and its associated coupling system, it is continued kneading and then, for example 1 minute later, the various additives are added. , including any additional coating or application agents, with the exception of the vulcanization system (sulfur and the sulfenamide type primary accelerator) When the bulk density of the reinforcing filler (or one of the reinforcing fillers if several fillers are used) ) is relatively small (for example, the silicas), it may be preferable to divide the introduction of the latter several times and, if necessary, its coupling system, to facilitate its incorporation into the elastomeric matrix, for example half and even about 3/4 of the load after the first minute of aisasado * and the rest after two minutes of kneading. The thermo-mechanical work is carried out in this way until a maximum temperature called "falling" is reached, for example between 150 ° C and 170 ° C. The mixing block is recovered It is obtained and cooled to a temperature lower than? 00 ° C After cooling a second thermomechanical stage is carried out in the same or in another mixer in order to subject the mixture to a complementary thermal treatment and obtain mainly a better dispersion of the load or reinforcer, naturally, certain additives such as, for example, stearic acid, antiozone wax, the agent * Antioxidant, zinc oxide or other additive, may not be introduced into the mixer, in whole or in part, more than in the course of this second stage of thermomechanical work. The 5- result of this first thermomechanical operation is then collected in an external cylinder mixer, at low temperature (for example between 30 ° C and 60 ° C) and the Vulcanization system; the whole is then mixed (productive operation) for some minutes, for example 0 between 2 and 5 minutes. The final composition thus obtained is then calendered for example in the form of a sheet or a plate, mainly by a characterization in the laboratory, or is even extruded, to form for example a profile of What is it? used for the manufacture of finished products, such as treads, crown layers, sidewalls, carcass layers, heels, protectors, air chambers or sealed inner tires for tubeless tires.

The vulcanization (or cooking) is carried out in a known manner at a temperature generally comprised between 130 ° C and 200 ° C, under pressure, for a sufficient time which may vary, for example, between 5 and 90 min. depending mainly on the cooking temperature, the system of: cross-linking adopted and the vulcanization kinetics of the composition considered. Needless to say, the invention relates to the rubber compositions described above both in raw (ie pre-cooking) and in-ready (or vulcanized) state (ie, after cross-linking or vulcanization). The compositions according to the invention can be used alone or in combination with any other rubber composition which can be used for the manufacture of tires III EXAMPLES OF THE MODALITY OF THE INVENTION III-1 Preparation of rubber compositions This is the procedure for all tests that follow, in two thermomechanical stages separated by an operation of rewind, as follows: in an internal mixer "i5e laboratory { 0.4 liters), of the" Btebury "type, filled to" 70% and whose initial temperature of the tank is At about 60 ° C, the elastomer (s) is introduced successively, approximately one minute later 2/3 of the reinforcing inorganic alloy and its associated coupling system, also one minute later the rest of the reinforcing filler, its system associated coupling as well as '-various additives with the exception of the antioxidant, the oxide of 10? Inc and the vulcanization system (sulfur and sulfenamide); a first thermomechanical work stage is carried out for approximately 3 to 4 minutes until reaching a maximum fall temperature of approximately 165 ° C; then the elastomer block is recovered and then cooled. Then, a second stage is carried out in the same mixer with the same conditions; the elastomer block is then subjected to a second thermomechanical work of a duration of 3 to 4 minutes as well, with the addition of the zinc oxide and the antioxidant, until reaching a maximum fall temperature of approximately 165 ° C. The mixture thus obtained is recovered and cooled and then sulfur and sulfenamide are added in an external mixer (oven-finisher) at 30 ° C, mixing the whole (productive operation) for 3 to 4 minutes.

The compositions thus obtained will then be calendered either in the form of plates (thickness of 2 to 3 mm) or of thin sheets of rubber for the measurement of their physical or mechanical properties, or in the form of directly usable profiles, after trimming and / or assembly to the desired dimensions, for example as semi-finished products for tires, in particular as treads. In most of the following tests, the reinforcing inorganic filler (silica and / or alumina) constitutes the total reinforcing filler used in a preferred proportion in a range of 50 to 100 pee; but naturally, in these tests, a fraction of the latter, preferably minority, could be replaced by carbon black. III-2. Tests A) Test 1 In this first test three rubber compositions (mixture of SBR and BR diene elastomers) reinforced with silica, intended for the manufacture of treads for tires are compared. The SBR elastomer is prepared in solution and comprises 26.5% styrene, 59.5% poly-1,2-butadiene residues and 23% poly-1,4-trans-butadiene residues, the BR elastomer comprises 93% of 1,4-cis residues. / > * $$ ta $ three compositions are identical with the «- - following differences: - composition No. 1: TESPT (6.4 pee) with DPC but without 1,2-DHP; '- composition No. 2: TESPT (6.4 pee) to which 5 ß "25 pee (ie 3.9% by weight with respect to the amount of TESPT) of 1,2-DHP and 1.5 pee of DPG are associated (i.e. about 1.9% by weight with respect to the amount of reinforcing inorganic filler); Composition No. 3: TESPT (6.4 pee) to which 10 0.5 pee (ie 7.8% by weight with respect to the amount of TESPT) of 1,2-DHP and 1.5 pee of DPG are associated. As component D the condensate is used here (aniline-butyraldehyde) Vanax 808 HP marketed by the company R.T. Vanderbilt, constituted mainly by ** 15 3, 5-diethyl-l, 2-dihydro-l-phenyl-2-propylpyridine of formula (I1-2) cited above (announced content of 1,2-DHP of at least 85% by weight). Composition No. 1 is the control of this test, contains a TESPT content of 8% by weight relative to the reinforcing inorganic load (6.4 pee of TESPT per 80 pee of silica), but is devoid of 1,2- DHP. In compositions No. 2 and No. 3, according to the invention, the total amount (ASPS + 1,2-DHP) represents less than 10% (respectively 8.3% and 8.6%) by weight with respect to the amount W - * 'of reinforcing inorganic load ^; As for the coupling system according to the invention (TESPT + 1,2-DHP + DPG), it is advantageously present in an internal proportion at 12% (respectively, 10.2% and 10.5%) by weight with * 5 -, r§ Regarding this amount of reinforcing inorganic filler. The tables 1 and 2 give the formulation of the different compositions (table 1 - proportions of the different products expressed in pee) and their properties before and after cooking (40 minutes at 150 ° C). Figure 1 * tó reproduces the curves of the module (in Mpa) according to the elongation (in%); these curves are called Cl, C2 and C3 and correspond respectively to compositions No. 1, No. 2 and No. ~ 3. Examination of the results in Table 2 shows that The compositions according to the invention (No. 2 and No. 3), compared to the control composition No. 1, present in the raw state a little different Mooney viscosity (therefore equivalent application properties), consequently more singeing times. short but that remain acceptable and in 20 state, they have significantly improved properties: - modules with higher deformations (M100 and M300) and higher ratio M300 / M100 (as known to those skilled in the art indicating better reinforcement); . { indicators of a lower rolling resistance for the treads); - «- equivalent breaking stresses. * The accompanying figure 1 confirms the previous results: for elongations of 100% and higher, all values of the module are clearly higher in the case of compositions No. 2 and No. 3 (curves C2 and C3); in the range of elongations, this clearly illustrates a better interaction between the reinforcing inorganic filler and the elastomer, E? In summary, all the results obtained after firing are representative of a better coupling between the reinforcing inorganic filler and the diene elastomer, in othersor if. "15 terms of an activation, by the 1,2-DHP and the guanidine derivative combined, of the coupling function of the ASPS B) Test 2 This test aims to show that it is possible, thanks to the activation provided by the 1,2-DHP and the derivative tO of guanidine, strongly decrease the amount of ASPS (TESPT), without penalizing the reinforcement properties of the Compions by the inorganic load.Then compare three rubber compions similar to those of the previous test 1, being these compions - * "- íe < < - identical with the following differences: compion No. 4: TESPT (6.4 pee) with DPG but without i, 2- - compion No. 5: TESPT (4 pee) with DPG but without 1,2-DHP; compion No. 6: TESPT (4 pee) plus 0.5 pee of 1,2-DHP (ie 12.5% by weight in relation to the amount of TESPT) and 1.5 pee of DPG. Only the compion No. 6 is therefore in accordance with the invention; the compion No. 4 is the reference compion of the prior art, the compion No. 5 represents a control with an identical proportion of TESPT with respect to the compion No. 6. Tables 3 and 4 give the formulation of the different compions and its properties before and after cooking. { 150 ° C, 40 min.). Figure 2 reproduces the curves of the module (in MPa) as a function of elongation (in%); these curves are designated C4 to C6 and correspond respectively to compions No. 4 to No. 6. In the compion No. 4 according to the prior art, the proportion of TESPT represents 8% by weight in relation to the amount of silica, which is 60% higher than the proportion of TESPT used in the compion No. 6 according to the with the invention In the case of compion No. 6, the amount of ASPS taken as the total amount (ASPS + 1,2-DHP) represents less than 6% (respectively, 5% and 5.6%) by weight in relation to the amount of reinforcing inorganic filler. As for the system 5 of coupling itself (ASPS + 1,2-DHP + DPG), is present in a proportion advantageously less than 10% ^ exactly 7.5%) by weight with respect to this same amount. The study of the different results shows that the The compion No. 6 according to the invention has, compared on the one hand with reference compion No. 4, equivalent behavior after firing, in spite of a clearly lower proportion of TESPT and compared on the other hand with the control compion No. 5, which contains 15 'the same amount of TESPT, but devoid of 1,2-DHP, globally superior behaviors: - modules in the strong deformations (M100, M300) and ratio M300 / M100 almost identical to those of the reference compion No. 4 and clearly superior to those of compion 20 witness No. 5; identical hysteresis losses (PH) for compions No. 4 and No. 6, on the other hand significantly lower than those of compion No. 5 and equivalent break properties. s * * * 1.a: figure 2 that is attached confirms well the effect of the activation of the coupling provided by the 1,2-DHP and the DPG: it is clear that the values of the module, for elongations of 100% and higher, are substantially identical for compions No. 4 and No. 6 (curves C4 and C6) Me * Süuy next), and clearly superior to those observed in the control compion No. 5. It can therefore decrease in a very sensitive way (from 6.4 pee to 4 pee) the amount of TESPT in the compions of 10 rubber according to the invention while maintaining the reinforcing properties at a substantially identical level.

Incidentally, the decrease in the proportion of silane imply unexpectedly, an increase in viscy in 15 crude state, but the variations observed are still acceptable; in particular, the person skilled in the art will know how to adjust, if necessary, the viscy increase in the raw state by adding a small amount of coating agent (see test 10 more 20 ahead). C) Test 3 This test shows that it is possible, thanks to the activation provided by a 1,2-DHP and a guanidma derivative, to replace a tetrasulfurized alkoxysilane (TESPT) j? - ~ x * í * W ^ m ^ $ £ § £ a, alcóxísilano "ÍB fcfmia o (TESPD), known as,» we active than the preceding, without practically affecting the properties of the rubber compositions.There are compared three rubber compositions similar to the 2 $ trials 1 and 2 precedents, these three being identical with the following differences: N ° 7: TESPT (6.4 pee) (with guanidine derivative but without 1,2-DHP); - composition N ° 8: TESPT (5.6 pee) (with guanidine derivative 10 p ro without 1,2-DHP); - Composition No. 9: TESPT (5.6 pee) plus 1.5 pee of 1,2-DHP (ie 8. 9% by weight in relation to the amount of TESPT) and 1.5 pee of guanidine derivative. Composition No. 7 is the control of this test (8% Jde 15"SSPT with respect to the weight of the reinforcing inorganic filler), composition No. 8, also not according to the invention, contains TESPD at an isomolar ratio with respect to the proportion of TESPT, ie for the two compositions No. 7 and No. 8, the same proportion of reactive triethoxysilane functions are used against silica and its surface hydroxyl groups.The composition No. 9 is Xa, the only composition according to the invention, its proportion of ASPS represents less than 8% (exactly 7%) by weight with cantidád4 e (TESPD + 1,2-DHP) less than 8% (exactly 7.6%) • with respect to this same amount; As for the coupling system according to the invention (TESPD + 1,2-DHP + DFG), its proportion advantageously represents less than 10%. { exactly 9.5%) by weight with respect to the amount of reinforcing inorganic filler. Tables 5 and 6 give the formulation of different compositions and their properties before and after cooking. { 150 ° C, 40 min.); Figure 3 reproduces the curves of the module (in Mpa) as a function of elongation (in%), these curves being called C7 to C9 and corresponding respectively to compositions No. 7 to No. 9. It is found that the composition No. 8, compared with the composition No. 7, has reinforcement properties after cooking (M100, M300 and M300 / M100 ratio) that are significantly lower, a lower resistance to breakage, as well as losses by major hysteresis: all this is due to the lower efficiency of the coupling (inorganic / elastomeric charge) of the disulfided alkoxysilane (TESPD) with respect to the tetrasulfurized alkoxysilane (TESPT). However, thanks to the addition of a small amount of 1,2-DHP in the composition No. 9, very sensitive improvement of the reinforcing properties is observed (M100, M300, M300 / M100, tension at break) and a decrease in PH, á i Are these properties reached at levels close to those observed in composition No. 7. The efficacy of l-2-DHP combined with the guanidine derivative, as "TESPD coupling activator, is also clearly illustrated by the curves of figure 3: curves C7 and C9 close and situated, for elongations greater than 100% clearly above curve C8 D) Test 4 This test confirms the previous results, f mainly those of test 1, using a 1, 2-DHP of different origin, available in the form of a heptaldehyde-aniline condensate whose major constituent is a 1,2-DHP (product marketed by Uniroyal Chemical under the name "Hepteen Base") .These two compositions are identical with the following differences : - composition No. 10: TESPT (6.4 pee), with DPG (1.5 pee) but without 1,2-DHP; - composition No. 11: TESPT (6.4 pee) with DPG (1.5 pee) plus 0.5 pee of 1, 2-DHP (ie 7.8% by weight with respect to the amount d of TESPT.) Each composition comprises 1.5 pee of guanidine derivative ie approximately 1.9% by weight with respect to the amount of reinforcing inorganic filler. The composition - * A. * v £ 9S TO.' C 0 0 is the 4test of this test, it contains a * TESPT proportion of 8% by weight with respect to the amount of organic load reinforcing (6.4 pee of TESPT for 80 Pee of Silice), but it is devoid of 1 , 2-DHP. In the composition. According to the invention, the amount of alkoxysilane and 1,2-DHP represents less than 10% (exactly 8.6%) by weight with respect to the amount of reinforcing inorganic filler; As for the coupling system according to the invention (TESPT + 1,2-DHP + DPG), it is advantageously 10 present in a proportion less than 12% (exactly 10.5%) by weight with respect to the amount of reinforcing inorganic filler. Tables 7 and 8 give the formulation of the different compositions (table 7 - proportions of the different products expressed in pee) and their properties before and after cooking (40 minutes at 150 ° C). L & Figure 4 reproduces the modulus curves (in MPa) as a function of elongation (in%); these curves are called CÍO and Cll and correspond respectively to the compositions N ° 10 and N ° ll. The examination of the results in Table 8 shows that the composition according to the invention (No. 11), compared to the control composition (No. 10), has a slightly different Mooney viscosity in the raw state (consequently equivalent use properties). ), a time of singeing 'sne lower - | § * f £! § satisfactory, and in cooked state ropíed & < | § significantly improved: - modules with higher deformations (M100 and M300) and an M300 / M100 ratio higher (indicators of a stronger reinforcement); ** lower hysteresis losses (PH); a tension in the equivalent break. The accompanying figure 4 confirms the above results: for elongations of 100% and higher, all values of the module are higher in the case of the composition according to the invention (compare the curves Cll and CÍO); for the range of elongations, the C • behavior clearly illustrates a better interaction between the reinforcing inorganic filler and the elastomer, thanks to the coupling system according to the invention. E Test 5 Three rubber compositions are prepared which comprise as a reinforcing inorganic filler a mixture (50/50) of silica and alumina; alumina is a reinforcing alumina such as that written in the aforementioned EP-A-0810258. These compositions are identical with the following deferences: "i- composition No. 12: TESPT with DPG but without 1,2-DHP; composition No. 13: TESPT activated by 1,2-DHP and DPG; Composition No. 14: TESPT activated by 1,2-DHP and DPG. Composition No. 12 is the control of the test, contains an ASPS content lower than 8% (exactly 6.6%) in relation to the weight of inorganic filler (6.5 pee of TESPT in relation to 99 pee of charge). Compositions No. 13 and No. 14, according to the invention, comprise the coupling system according to the invention (ASPS + 1, 2-DHP + DPG) at a ratio that is also, advantageously, less than 8% . { exactly 7.9%) in relation to the weight of inorganic load w total reinforcer. Tables 9 and 10 give the formulation of the different compositions and their properties before and after cooking 40 min. at 150 ° C) + Figure 5 reproduces the curves of the module as a function of elongation (curves called C12 and 15 C14 and corresponding respectively to the compositions No. 12 and No. 14). The examination of the results shows, for the compositions of the invention, of supposedly higher Mooney viscosities (which can be reduced by the addition of a coating agent tea), but in the cooked state improved properties: modules M100 and M300, ratio M100 / M300 higher, lower PH losses. Figure 5 confirms these results with, for elongations of 100% and greater, superior modules for the compositions of the invention (curves) < %? V * € 13 and I heard, above all * lá? curve C12). It is observed on the other hand that the best results # 1100, M300 ,? ratio M300 / M100, PH) are obtained with the "Condensate butyraldehyde-aniline having the highest content of 1,2-DHP (Vanax 808 HP), as confirmed by the curves of Figure 5 (curve C13 above) of curve C14) F) Test 6 In this test, the test results are confirmed 10 above in the presence of another reinforcing alumina (according to the aforementioned EP-A-0810258 application), different BET surface (proportion of ASPS: 6% by weight relative to the amount of reinforcing inorganic filler). The two compositions tested are identical with the following differences: composition No. 15: TESPT with DPG but without 1,2-DHP; composition No. 16: TESPT activated by 1,2-DHP and DPG. Composition No. 15 is the control of the test. In the composition No. 16 according to the invention, the total amount of the coupling system (TESPT + 1, 2-DHP + DPG) is advantageously less than 8% (exactly 7.5%) by weight in relation to "the amount of charge Inorganic Table 11 and 12 give the formulation of the compositions and their properties before and after cooking - Id i. 3 150 ° C) »Xa figure 6 reproduces the curves of the module as a function of elongation (called C15 and C16).

«* The results show that the composition of the invention, compared to the control, presents in state J • 5 crude a nearly identical viscosity, a scorching time? Feducido but satisfactory, and in cooked state indicating properties of a better coupling; M100, M300 modules, higher M300 / M100 ratio and clearly reduced PH losses. Figure 6 confirms these results, with a curve C16 located clearly above the control curve C15. G) Test 7 This test demonstrates that the presence of a "guanidine derivative (DPG or DOTG) is an essential characteristic in the Coupling System according to the invention. Three identical rubber compositions are compared with the following differences: Composition No. 17: TESPT with DPG but without 1,2-DHP; T composition No. 18: TESPT with 1,2-DHP but without derivative of * 20 guanidine; - composition No. 19: TESPT with DPG and 1,2-DHP; * composition N ° 20: TESPT with DOTG and 1,2-DHP. Only compositions No. 19 and No. 20 are therefore in accordance with the invention; the composition No. 17 is the witness # * * according to the prior art. Tables 13 and 14 give the formulation and properties of these compositions before and after cooking (40 mes at 150 ° C). Figure 7 shows the curves of the module as a function of elongation 5. { called C17 to C20 and corresponding respectively to compositions No. 17 to No. 20). The study of the different results shows that the *, compositions of the invention, compared to the control composition No. 17, have clearly improved properties in the baked state: M100, M300 modules and M300 / M100 ratio clearly superior, PH values significantly reduced, clear indicators of improved coupling, < Jomo is confirmed by FIG. 7: curves C19 and C20 located at an angle above the control curve C17. As for the composition No. 18, devoid of guanidine derivative, these properties appear globally degraded in relation to those of the compositions of the invention, both in the raw state and after cooking. { clearly higher viscosity; most important PH losses; lower M300 / M100 ratio; . curve C18 r? slightly below curve C17). These results therefore clearly demonstrate that in the absence of the guanidine derivative, 1,2-DHP has no effect on the coupling agent.

This test shows that it is possible, thanks to the strong activation provided by the 1,2-DHP and the guanidine derivative combined, to decrease very significantly the quantity of ASPS (here, disulfurized alkoxysilane TESPD) maintaining the reinforcing properties a sensibly identical level. The three compositions tested are identical with the following differences: composition No. 21: TESPD (5.6 pee) with DPG but without 1,2-DHP; "• - composition No. 22: TESPD (3.5 pee) with DPG but without 1,2-DHP; - composition N ° 23: TESPD (3.5 pee) with DPG (1.5 pee) and 1,2-DHP (0.5 pee ie 14.3% by weight in relation to the amount of TESPD). Composition No. 21 is the reference of the prior art; it is observed that its proportion of ASPS is very clearly (60%) higher than the proportion of ASPS of the composition according to the invention No. 23. In this composition of the invention No. 23, the total amount (TESPD + 1, 2- DHP) represents less than 6% (exactly 5%) by weight relative to the amount of silica. As for the coupling system itself (ASPS + 1, 2-DHP + DPG), it is advantageously present in a proportion of less than 8% (exactly 6.9%) by weight in relation to this same amount.

- Tables 15 and 3 give the formulation of the different compositions, their properties before and after cooking. { 150 ° C, 40 min.). Figure e reproduces the modulus / elongation curves (curves designated C21 to C23 and corresponding respectively to compositions No. 21 to No. 23). The results show that the composition No. 23 according to the invention has, compared to the reference composition No. 21, equivalent cooking behaviors despite a clearly lower proportion of TESPD: modules M100, M300, ratio M300 / M100 , properties at break as well as substantially identical PH losses. As for the control composition No. 22 which contains the same proportion of TESPD as the composition of the invention, it shows clearly degraded behavior in the absence of 1,2-DHP. Figure 8 confirms these results, presenting the composition of the invention (curve C23) values of the module slightly higher than those of the reference composition No. 21 (curve C21), well above those of the control composition No. 22 depleted of 1,2-DHP. I) Test 9 In this test, the invention is performed with an ASPS different from the symmetric ASPS used in the tests MR tlt riore ^ in this case an ASPS of the polymer type. "* ** * For this, two identical compositions are prepared with the following differences: - composition No. 24: ASPS with DGP but without 1,2-DHP;" 5 t - composition No. 25: ASPS activated by 1,2- DHP and DPG. x Composition N 24 is the witness of this test; composition No. 25, according to the invention, comprises the coupling system according to the invention (ASPS + 1,2-DHP + guanidine derivative) in a preferred proportion 10 less than 12% (exactly 10.5%) in relation to the weight of inorganic filler. The ASPS tested responds to the mentioned formula (according to WO 96/10604).

Tables 17 and 18 give the formulation of two compositions and their properties before and after cooking} (40 min at 150 ° C). Figure 9 reproduces the module / elongation curves (called C24 and C25). The results show that the composition according to i > *. coaparada '.,? la * control composition, presents pre-cooking properties that are substantially identical and improved properties after cooking: modules in the M100 and M300 strong deformations, higher M300 / M100 ratio. { indicators of a higher reinforcement), lower PH losses (therefore better). Figure 9 confirms the results, with, for elongations of 100% and greater, heats of the module clearly superior for the composition ** of the invention (curve C24). All this clearly illustrates a better interaction between the inorganic charge and the elastomer. Test 10 In a known manner, a significant reduction in the proportion of ASPS has the risk of causing a viscosity increase in the raw state of the rubber compositions, which increase may penalize its industrial application. This test demonstrates that it is possible to alleviate the drawback with the addition, to the compositions of the invention, of an agent for coating the inorganic filler. In this case, according to a particularly preferred embodiment of the invention, a hydroxylated polyorganosiloxane, in particular an α, β-d ?hydroxy-polyorganosiloxane, is associated with ASPS as the coating agent, in accordance with the teaching of the application for EP-A-0 764 072.

»'' M For this test six compositions are prepared, with the following differences: - composition No. 26: TESPT (6.4 pee) with DPC but without 1,2-DHP; - composition No. 27: TESPT (4 pee), with DPG but without 1,2-DHP; - composition No. 28: TESPT (4 pee) activated by DPG and 1.2 ~ DHP - compositions No. 29 to No. 31: identical to composition No. 28 but also containing variable proportions (0.5 to 2.4 pee) of different coating agents (alkyltrialkoxysilanes or a,? - dihydroxy-polyorganosiloxane). The composition No. 26 is the reference of the prior art, the composition No. 27 represents a control with an identical proportion of TESPT in relation to the compositions according to the invention No. 28 to No. 31. Tables 19 and 20 give the formulation of the different compositions and their properties before and after cooking (150 ° C, 40 min.). The coating agents have been incorporated into the compositions according to the invention at the same time as the ASPS (non-productive stage). In these -compositions according to the invention (No. 28 to No. 31), the total amount of the coupling system (TESPT + 1, 2-DHP + DPG) advantageously represents less than 8% (exactly 7.5%) in relation to the load weight inorganic The results of table 20 require the following comments: - $$ • firstly it is observed that the dissolution of the proportion of ASPS in the control composition No. 27 causes, with reference to the reference composition No. 26, no general degradation of the properties, both in the raw state Ipamento viscosity sensitive, from 76 to 96 MU) with or after firing: strongly diminished M100 and M300 modules, higher PH losses; - thanks to the addition of 1,2-DHP to composition No. 28 and consequently to the combined action of DPG and 1,2-DHP, a very clear improvement of the properties after cooking is observed. they conceal values (mainly M100, M300, PH) almost identical to those of the starting reference. { composition No. 26); however, the increase in crude viscosity (76 to 96 MU) observed above is not compensated more than very weakly (from 96 to 91 MU) by the addition of 1,2-DHP; - this increase in the viscosity in the raw state is on the contrary completely corrected, maintaining the properties after cooking at a level substantially identical to that of the reference composition (No. 26), thanks to the addition, to the compositions according to the invention No. 29 to No. 31, of the coating agent (return to values of about 70 J, to 80 UM). In particular, the excellent commitment of obtained with 1 * dsposition according to the invention »No. 31, despite a very low proportion (internal to 1 pee) of oil a, β-dihydroxy-polyorganosiloxane as the coating agent. -i5 $.) Test 11 The invention is illustrated herein by rolling tests of radial carcass tires. - * dimension 175/70 R14, manufactured in a known manner and which are • identical in all respects except for the constitution of the ** "f composition of rubber constituting the tread.

The compositions tested are identical to the compositions 'N ° 26, N ° 28 and N ° 31 of test 10 above, with the small difference that they also contain a low proportion (6 pee)? of carbon black (N234), used essentially as 15 coloring agent and anti-UV, and that have been prepared, for the needs of these tire tests, in appropriate mixers of higher capacity. The tires prepared in this way are prepared for road rolling, in a Citro n Xsara brand vehicle, until the wear due to rolling reaches the wear tokens arranged in the grooves of the treads.

In a manner known to those skilled in the art, the wear resistance of the rubber composition, during rolling of the tire, is directly related to - * - »AK *% of the reinforcement provided by the reinforcing load, is the coupling ratio (load / elastomer) obtained. In other words, the measurement of the wear resistance is an excellent indicator, if not the best since 5 is evaluated on the final manufactured product, of the behavior of the coupling system used. It is observed after rolling that the tires equipped with treads according to the invention. { corresponding to the compositions No. 28 and No. 31) show a behavior almost identical to that of the witness tire (corresponding to composition No. 26), running substantially the same mileage, despite a strongly reduced proportion of coupling agent (4.0 pee in * place of 6.4 pee). This equivalent wear resistance has only been possible thanks to the strong activation of the coupling provided by the 1,2-DHP compounds and guanidine derivative in combination. The composition No. 31, which incorporates the polyorganosiloxane coating agent, also offers the advantage of an easy industrial application. { reduced plasticity in the raw state) in relation to "the composition No. 28. The invention therefore makes it possible to have tire treads having very good strength.; 1 wear combined with low rolling resistance, k. ,, - * £ W - " in the presence of a proportion of ASPS (in particular? ESPT) noticeably very reduced. In conclusion, all the previous results are representative of an improved coupling between the load * 5 inorganic reinforcing and diene elastomer when used, associated with ASPS, both a 1,2-DHP and a guanidine derivative. In other words, these results are representative of an activation with 1,2-DHP and the combined guanidine derivative, of the function of 10 coupling performed by ASPS. Thanks to this activation, the reduction of the quantity of ASPS, mainly TESPT, can be considered from now on, maintaining the coupling properties and consequently the wear properties at levels 15 equivalents; The overall cost of rubber compositions can thus be reduced, as can the tires that contain them. A reduction in the proportion of ASPS also has the advantage, from the point of view of the environment 20. { degassing of VOCs - "Volatile Organic Compounds "), to lead to the decrease in the proportion of *) alcohol (ethanol in the case of TESPT) emitted during the manufacture of the rubber compositions, or during the cooking of rubber articles incorporating these compositions The invention thus allows, if a high proportion of ASPS is retained, to obtain a higher coupling level, and therefore to achieve an even better reinforcement of the rubber compositions by the reinforcing inorganic filler. The new coupling system (inorganic filler / diene elastomer) according to the invention thus offers the compositions of the invention a compromise of particularly advantageous properties compared to the prior art compositions reinforced with an inorganic filler. Table 1 «* SH ^ diluted with 13.5 pee of aromatic oil (ie a totaá¡ i B .5 pee); . { 21 BR có? I, 4. % of 1.2; 2.7% trans; 93% Cs-1.4 (Tg - -106 ° C); (3) silica type "HDS" - Zeosil 1165 MP from the company Rhodia f 'and in the form of microbeads (BET and C : approximately 160 m2 / g); (4) 1,2-DHP of formula II-2 (Vanax 808 HP from R.T. Vanderbilt); (5) N-1, 3-d? Met? Lbutil-N-phenyl-para-phenylenediamine 10 (Santoflex 6-PPD from Flexsys); (6) Diphenilguanidma (Vulkacit from Bayer); (7) N-c? Clohex? L-2-benzot? Az? L-sulfenamide (Santocure CBS from Flexsys).

Table 2 15 ^ k twenty ? '-' * f Table 4 fifteen- Table 5 • 10 (1) to (7) idem table 1 Table 6 'fifteen,. twenty ? * Fc: ^ * £ sM Table 7 (1) to (7) idem table 1; (8) "Hepteen base" condensate (Uniroyal Chemical company) Table 8 15 'Pbis) alumina "CR125" from Baikowski company; (in powder form - BET: approximately 105 m2 / g. (9) 1,2-DHP of formula II-2 (Vulkacit 576 of the company • Báyer) twenty ! li Table 10 - * - *! • ?OR * 15, «w FOR Table 11 , (1) to (7) idem table 1; (3a) alumina "APA-100RDX" from the company Condea (in powder form - BET: approximately 85 m2 / g). Table 12 '*. " Table 3.3 (1) to (7) idem table 1; (10) DOTG of the Vanderbilt company, formula (III-2; Table 14 Table 19 10 (1) to (7) idem table 1, 15 (13; octyltriethoxysilane-Dyyny Otheo 'from Huís society); . { 14) hexadecyltrimethoxysilane ("YES116" from the company Degussa); 20 (15) a,? -dihydroxy-polydimethylsiloxane ("Rhodorsil 48V50" oil from the company Rhodia). - * &4SÍ Tálala 20 It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (1)

1. In the description of the invention as above, the content of the following claims is claimed as property: 1. Composition of rubber usable for the manufacture of tires Ae, characterized in that it is based on at least: (i) a diene elastomer, (ii) an inorganic filler as a reinforcing filler, (iii) a polysulfurized alkoxysilane ("ASPS") as a coupling agent (filler) 10 inorganic / diene elastomer) to which are associated (iv) a 1,2-dihydropyridine (1,2-DHP) and (v) a guanidine derivative. 2. Composition according to claim 1, characterized in that the diene elastomer of the group constituted is chosen 15 by polybutadienes, polyisoprenes, natural rubber / butadiene copolymers, isoprene copolymers and mixtures of these elastomers. Composition according to claims 1 or 2, characterized in that the reinforcing inorganic filler is a siliceous or aluminous b load, preferably a highly dispersible silica. * 4. Composition according to any one of the Claims 1 to 3, characterized in that the ASPS is a bisalkoxy (C? -C4) -silylalkyl polysulphide (Ci- v -. . The composition of claim 1, characterized in that 1,2-DHP is present in the form of a condensate (primary aldehyde-amine). 6. Composition according to any one of claims 1 to 5, characterized in that the 1,2-DHP is an N-phenyl-1,2-dihydropyridine. Composition according to any one of Claims 1 to 6, characterized in that the quantity of? 1 ^ 2-DHP represents between 1% and 20% by weight in relation to the amount of ASPS. Composition according to any one of Claims 1 to 7, characterized in that the total amount of ASPS and 1,2-DHP represents less than 10% by weight '15 in relation to the amount of reinforcing inorganic filler. Composition according to any one of claims 1 to 8, characterized in that the giJanidine derivative is N, 'diphenylguanidine (DPG). 10. Composition according to any one of 2fr 'Claims 1 to 9, characterized in that the amount of guanidine derivative represents between 0.5 and 4% by weight with respect to the amount of reinforcing inorganic filler. 11. Composition according to any one of claims 1 to 10, characterized in that the amount The amount of guanidine represents between 2% and 20% by weight relative to the amount of reinforcing inorganic filler. 12. Composition according to any one of claims 2 to 11, characterized in that the diene elastomer is a copolymer of butadiene-styrene (SBR) having a styrene content comprised between 20% and 30% by weight, a content of vinyl bonds of the butadiene part comprised between 15% and 65%, a content of 10 trans-1,4 bonds comprised between 20% and 75% and a glass transition temperature comprised between -20 ° C and -55 ° C. 13. The composition according to claim 12, characterized in that the SBR is a SBR prepared in solution. 15"14. Composition according to claims 12 or 13, characterized in that the SBR is used mixed with a polybutadiene preferably having more than 90% of cis-1, 15. Composition according to any one of the 2 claims 1 to 14 , characterized in that the reinforcing inorganic filler constitutes the entire reinforcing filler 16. Composition according to any one of claims 1 to 14, characterized in that the Inorganic reinforcer mixed with carbon black. 17. Composition according to any one of claims 4 to 16, characterized in that the ASPS is bisalkoxy (C? -C) -silylpropyl polysulfide. '5' 18. Composition according to claim 17, characterized in that the ASPS is disulfide or bis-triethoxysilylpropyl tetrasulfide. Composition according to any one of claims 5 to 18, characterized in that the aldehyde is 10 choose from the condensate between the C2-C? 2 aldehydes. Composition according to claim 19, characterized in that the aldehyde is selected from poropionaldehyde, butyraldehyde, valeraldehyde and hexaldehyde. 21. The composition according to claim 20, characterized in that the aldehyde is butyraldehyde. 22. Composition according to any one of claims 5 to 21, characterized in that the content of 1,2-DHP in the condensate is greater than 50% by weight. 23. Composition according to any one of claims 6 to 22, characterized in that 1,2-DHP is 3,5-diethyl-1,2-dihydro-1-phenol-2-propylpyridine. Composition according to any one of the "<" "claims 1 to 23, characterized in that it comprises an inorganic filler coating agent. 25, Composition according to claim 24, characterized in that the coating agent is a hydroxylated polyorganosiloxane. 26. ' Composition according to claim 25, 5 characterized in that the coating agent is a t a, β-dihydroxy-polyorganosiloxane, preferably used in a proportion lower than 1 pee. 27. Composition according to any one of claims 1 to 26, characterized in that it is in a vulcanized state. 28. Process for preparing a composition of vulcanizable rubber with sulfur and usable for the manufacture of tires, characterized in that it is incorporated in (i) a diene elastomer, at least: (ii) an inorganic filler as a reinforcing filler; (iii) a polysulfurized alkoxysilane ("ASPS"); (iv) a 1, 2-d? hydropyridine ("1 / 2-" DHP ") and (and) a guanidine derivative and because the whole- is kneaded thermomechanically, in one or several stages, until reaching a maximum temperature comprised between 120 ° C and 190 ° C 29. Process according to claim 28, characterized in that the diene elastomer is selected from the group consisting of polybutadienes, polyisoprenes, natural rubber, butadiene copolymers, isoprene copolymers and , « ; - > * * ip zc * tf dfel these elastomers. *** "* 30, Process according to claim 28 or -29 characterized in that the reinforcing inorganic filler is a siliceous or aluminous filler, preferably a highly dispersible silica. 31; Process according to any one of claims 28 to 30, characterized in that the ASPS is a bis (C1-C4) -silylalkyl (Ci-Cio) • 32 bisalkoxy polysulphide. Method according to any one of the claims from 28 to 31, characterized in that 1,2-DHP is present in the form of a condensate (primary aldehyde-amine). 33. Process according to any one of claims 28 to 32, characterized in that 1,2-DHP 15β an N-phenyl-1,2-dihydropyridine. 3 . Process according to any one of claims 28 to 33, characterized in that it represents the amount of 1,2-DHP between 1% and 20% by weight with respect to the amount of ASPS. 35. Method according to any one of claims 28 to 34, characterized in that it represents the total amount of ASPS and 1,2-DHP less than 10% by weight in relation to the amount of reinforcing inorganic filler. 36. Procedure according to any one of the §a -3,5- | i til-l, 2-dihydro-l-phenyl-2-propylpridine. 44. Process according to any one of claims 28 to 43, characterized in that it comprises an inorganic charge coating agent. 45. Method according to claim 44, characterized in that the coating agent is a hydroxylated polyorganosiloxane. 46. Method according to claim 45, characterized in that the coating agent is a 10 # ,,? -dihydroxy-polyorganosiloxane, preferably used in a proportion lower than 1 pee. 47. Method according to any of claims 28 to 46, characterized in that the maximum mixing temperature between 130 ° C and 180 ° C is included. 48. Use of a rubber composition according to any one of claims 1 to 26, for the manufacture of tires or semifinished rubber products intended for tires, these products being chosen 20 semi-finishes in particular of the group consisting of treads, sublayers, crown layers, sidewalls, carcass layers, heels, protectors, inner tubes and sealed inner tires for tubeless tires. The rubber composition according to any of claims 1 to 26. 50. Vulcanized tire, characterized by a rubber composition according to claim 27. 51. Semi-finished product. - Rubber tire finish, characterized in that it comprises a rubber composition of - "- according to any one of claims 1 to 26," ¿,, 1. this particular semi-finished product being selected from the group consisting of treads, sub-layers, crown layers, sidewalls, carcass plies, heels, protectors, * '* inner tubes and sealed inner tires for tubeless tires. 15 52. Semi-finished products according to claim 51 characterized in that it is in the form of a tire tread. 53 Tire tread according to claim 52, characterized in that it comprises a rubber composition according to any one of the 3ft 'claims 12 to 14. 54. Method for coupling an inorganic filler and a diene elastomer, in a rubber composition, characterized in that it incorporates (i) a diene elastomer, at least. (n) an inorganic charge as charge i i ii) a polysulfurized alkoxysilane ("ASPS"); iv) a 1,2-diJ? idropipdine ("1,2-DHPH) and (v) a fuanidine derivative and because the whole is kneaded termoancántntente, have one or several stages, until reaching a maximum temperature 1 'H "comprised between 120 ° C and 190 ° C J 55. Method according to claim 54, characterized in that the diene elastomer is selected from the group consisting of polybutadienes, polyisoprenes, natural rubber, butadiene copolymers, isoprene copolymers Y 10 mixtures of these elastomers. 56. Process according to claims 54 or 55, characterized in that the reinforcing inorganic filler is a siliceous or alummose filler, preferably a highly dispersible silica. 57. Method according to any one of claims 54 to 56, characterized in that the ASPS is a bisalkoxy (C? -C4) -silylalkyl (Ci-Cio) polysulfide. 58. Method according to any one of claims 54 to 57, characterized in that it is present 20 1-DHP in the form of a condensate (primary aldehyde-amine). 59. Method according to any one of claims 54 to 58, characterized in that the 1,2-DHP is an N-phenol-1, 2-d? H? Drop? Ridma. 60 ', Process according to any one of claims 54 to 59, characterized in that the guanidine derivative is N, N'di-phenylguanidine (DPG). 61. Combination use of a 1,2-dihydropyridine and a guanidine derivative / in a rubber composition based on diene elastomer reinforced by an inorganic filler, to activate the coupling function (inorganic filler / diene elastomer) of an alkoxysilane polysulfurized 62. Coupling system (inorganic filler / diene elastomer) for a rubber composition based on diene elastomer reinforced with an inorganic filler, characterized in that it is constituted by the combination of a pfOlisulfurized alkoxysilane ("ASPS"), a guanidine derivative and a 1,2-dihydropyridine ("1,2-DHP"). 63. Coupling system according to claim 62, characterized in that the ASPS is a bis- * alkoxy (C? -C4) -silylalkyl (Ci-Cio) polysulfide. 64. Coupling system according to claim 62 or 63, characterized in that 1,2-DHP is present in the form of a condensate (primary aldehyde-amine). 65. Coupling system according to any one of claims 62 to 64, characterized in that the 1,2-DHP is an N-phenyl-1,2-d? Hydropyridine. ? H « 66. Coupling system according to any one of claims 62 to 65, characterized in that it represents the amount of 1,2-DHP between 1% and 20% by weight in relation to the amount of ASPS. 67. Coupling system according to any one of claims 62 to 66, characterized in that the guanidine derivative is N, N'-diphenylguanidine (DPG). 68. Coupling system according to any one of claims 63 to 67, characterized in that the ASPS is a bis-alkoxy (C? -C) -silylpropyl polysulfide. $ 6. Coupling system according to any one of claims 64 to 68, characterized in that the aldehyde is chosen from poropionaldehyde, berylaldehyde, valeraldehyde and hexaldehyde. 70. Coupling system according to claim 69, characterized in that the aldehyde is butyraldehyde. * 71. Coupling system according to any one of claims 64 to 70, characterized in that the content of 1,2-DHP is greater than 50% by weight in the condensate. 72. Coupling system according to any one of claims 65 to 71, characterized in that the 1,2-DHP is 3,5-diethyl-l, 2-dihydro-l-phenyl-2-propylpyridine. * j "1 j> Ge" * coupling of a reinforcing inorganic filler and a diene elastomer in a rubber composition based on X-5 diene elastomer reinforced by an inorganic filler. 10 fifteen • r 30" 'K which is associated with one, - rop r na and a guanidine derivative. Tire or semi-finished product for tire comprising a rubber composition according to the invention. Coupling system (inorganic filler / diene elastomer) for a rubber composition, diene elastomer base reinforced by an inorganic filler, constituted by the combination of an alkoxysulfonated alkoxysilane, a guanidine derivative and a 1,2-l, * Idá.hidropirid? na. * < * > A ^ ^ a? HÉaH